Final answer:
The appropriate noun to fill in the blank is 'culpa.'
Step-by-step explanation:
The appropriate noun to fill in the blank in the sentence is culpa. The complete sentence would be: 'Te pido perdón. Yo tengo la culpa de todo.'
'Culpa' translates to 'guilt' in English. In this context, the speaker is apologizing and taking responsibility for everything, implying they feel guilty. The other options, 'sinvergüenza' means 'shameless,' 'relación' means 'relationship,' and 'pintura' means 'paint.'
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